Adapting To Summer Heat
2012-07-08This year, the summer is dry and warm in Romania, in some places it can also be called hot (for me, hot is somewhere beyond 35 degreees Celsius). Staying indoors can be quite a torture: air is not moving enough, green house effect from the windows and so on. I'm the type of guy who love comfort but doesn't want to pay much for it. To achieve comfort with minimal costs I "sacrifice" time and energy on thinking about solutions. Since this is the 3rd (?) week of heat I had a real motivation to seek methods of achieving tolerable temps in my room and at work. Results did come so they are worth sharing with everyone who's not a termo-masochist. Let's start with some basic physics principles (if you don't like theory, you can skip to the practical side).
- Warm air has the tendency to rise. Cold air has the tendency to replace warm air.
- The lower part of a window is where cold air circulates. The middle part is where there is almost no air moving. On the upper part is where warm air circulates.
- Our body cools itself through perspiration. Tiny particles of water evaporate from the surface of the skin. The air surrounding the body gets saturated with humidity. In this case, evaporation cannot be sufficient for cooling (air doesn't accept more water from the body), so the body will raise water output. That water will also not evaporate, so it remains on the surface of the skin. This is transpiration and we don't like it, especially at work. So, drinking more water will mitigate only the symptoms but not the cause, so it's an inefficient and costly method.
- Objects store heat. Much more heat than air stores. This is a problem because when the night comes and outside temp drops, the room remains hot due to objects giving out the heat they assimilated during the day. I heard people say "the hot air is blocked inside the house". But that's wrong. You can change the air in seconds and after stopping ventillation, still have a hot room. What is important is to prevent heat getting stored during the day. Walls are only one part of this. There is also the furniture whitch can store lots of heat.
- Electronics generate heat. Bigger power consumption equals bigger heat output. Electronics can be regarded as heaters.
- Objects exposed to sunlight will heat up. Dark ones heat to higher temperatures while lighter ones reflect light and tend to heat up less.
- Heating and cooling efficiency highly depends on exposed surface.
- Ventilation. You can use commercially available fans or anything you find suitable to move air. I took a computer power supply and two fans that I had taken from defective PSUs. Moving air takes away the water-saturated air that surrounds the body thus enabling efficient self-cooling. Avoid fans that blow you out of your room. This is bad for your health. Keep a certain distance from the fans (in my case, it's at least one meter).
- Windows. This is very important. During the day, outside temperature is higher than inside temperature. Based on points 1 and 2, you can understand why it's important not to open the windows while outside is hot - cold air from inside will go out and warm air will come in. Where I live, outside temp goes equal around 10 A.M. Starting from this hour, I close the windows until 9 P.M. when outside temp equals inside temp again and then starts lowering.
- Window blinds. Use blinds that are of lighter color: white, yellow, beige etc. If yo use dark colored blinds, you end up in a greenhouse-like environment.
- Forced room cooling. No, I'm not referring to air conditioners. In the evening, when you open the windows, you can place the fans at the bottom of the window frame. This way cool air enters the room faster thus allowing hot air to be evacuated sooner. In case you are measuring temps somewhere inside the room and see no or almost no change, remember that first the furniture and walls have to get rid of the stored heat. The difference that fans make is that the temperature will drop sooner (but still not until 1-3 A.M.). but not instantly. Another thing is that fans will blow cooler air at you and this is good :)
- Electric and electronic devices. Keep and eye on power hungry electronics. These days I use only an LED tube (10 Watts) (in worst case you can use fluorescent tubes or bulbs). I also gave up on using my audio amplifier (100 W) and switched to 2 tiny speakers (cca. 5 W). The computer's operating system is set to Power Saving. This leads to smaller performance but much less heat produced.
- Extra cooling with water. Take a few bottles and fill them up with cold water from the tap. Then, place them behind the fans. Air coming from fans will be a few degrees cooler than surrounding air. It might not seem much, but it still is a gain. Try to make a cold aisle from where the fans take the cool air this way achieveng more efficient cooling. I did not mention ice because producing ice is coslty and the refrigerator dumps the extracted heat from water into its environment (your apartment).
- Cooling surface. Try to expose maximum body surface to cooling. Less clothing is only one thing. Try to sit on a chair that lets you skin breathe. If possible, from time to time sit in a manner that your back isn't in contact with any insulating material. Just think about how many % of your total skin surface is represented by your back.